This invention pertains to containers and more particularly involves thermoplastic containers with improved specific structure in the lip sealing area of the container top opening. The container is of the type generally disclosed in U.S. Des. Pat. No. D252,796 to Vincent E. Fortuna and Matt Lerner, issued Sept. 4, 1979, entitled "CONTAINER FOR FOOD PRODUCTS OR THE LIKE".
The container disclosed in the aforementioned Fortuna et al patent utilizes a large top opening defined by a flat-topped outer annular surface which has a rolled rim at its outer periphery (see FIG. 2). The rolled rim terminates in a short, inset vertical wall portion which extends downwardly a short distance and then diverges conically downward and outward to merge with the slightly-tapered vertical sidewall of the container. The flat-topped annular top portion, having a hemispherical or rolled outer rim, provides the sealing surface for the container closure member (not shown).
In the containers of the type disclosed in the Fortuna et al patent, the most common type of closure member utilized to seal off the container opening is the crimpable type usually comprising a thin metal foil, paper or plastic cap which is attached to the container by an adhesive plus the crimping action of the cap over the rolled outer rim of the container.
The problem with this type of container/cap structure has been the difficulty of obtaining a crimped cap that is properly sealed and yet can be removed by the consumer without need for undue ripping, tearing and/or cutting.
The present invention provides an improved container lip design offering the advantage over conventional container design that the present container can be sealed much better than conventional containers and yet have an easier opening top closure.